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91.
G. Gray Eaton Deanne F. Johnson Barbara B. Glick Julie M. Worlein 《Primates; journal of primatology》1986,27(2):141-150
We have quantitatively documented the development of sex differences in the behavior of juvenile Japanese macaques (1 to 2
years of age). Mothers treated their offspring differently by sex, i.e., mothers of males broke contact with them more frequently
than did mothers of females. Juvenile males played more, and mounted other macaques more frequently; juvenile females groomed
their mothers more and were also punished by other group members more frequently than were males. Males showed a pattern of
decreasing interactions with their mothers, but females increased the frequency of their maternal interactions. These patterns
appear to presage the life histories of the sexes. However, comparisons with other species of nonhuman primates indicate that
although sex differences in behavior are common, the variability among species severely limits cross-specific generalizations. 相似文献
92.
Barbara Beckerman Glide G. Gray Eaton Deanne F. Johnson Julie Worlein 《International journal of primatology》1986,7(2):139-155
The behavioral interactions of 22 infant and mother Japanese macaques with other group members were studied. Focal-animal
observations were made from the time of each infant’s birth until 1 year of age. Infants and mothers both displayed exceedingly
strong preferences for associating with matrilineal kin and, specifically, for female kin. The degree of genetic relatedness
was positively correlated with levels of spatial proximity, contact, grooming, aggression, and play. Overall frequencies of
interactions with nonkin were very low, and partner sex was not an important factor in interactions with nonkin. There were
no significant differences between male and female infants in interactions with kin versus nonkin. There was only one significant
difference between male and female infants in interactions with males versus females: female infants showed stronger preferences
for initiating proximity with females over males than did male infants. Because mothers provide the focal point for infant
interactions during the first year of life, we compared the behavior of infants and mothers. Mothers were the recipients of
more social interactions than were infants, mothers engaged in more grooming than did infants, and infants engaged in more
social play than did mothers. These findings are only partially consistent with kin-selection theory, and the inadequacies
of studying matrilineal kin discrimination to test kin selection are reviewed. The near-absence of infant sex differences
in associations with social partners suggests that although maternal kin other than the mother are important to infant socialization,
they probably do not contribute to the development of behavioral sex differences until after the first year of life. 相似文献
93.
Glick Barbara Beckerman Eaton G. Gray Johnson Deanne F. Worlein Julie M. 《International journal of primatology》1986,7(5):467-479
Quantitative data are presented on the effects of subject sex, partner sex,and kinship on the social interactions of 18 juveniles of the Oregon troop of Japanese macaques (Macaca fuscata).Data on these subjects as infants were also used to detail maturational changes in partner sex preferences. Nine males and
nine females, whose multiparous mothers represented a cross section of dominance ranks, were observed using a focal-animal
technique. Juveniles of both sexes engaged in more proximity, contact, grooming, mounting, aggression, and social play with
kin than with nonkin partners. They initiated less contact with females and more contact with males during their second year.
They initiated more grooming and aggression during their second year than their first year, with females displaying a strong
preference for grooming females and males specifically aggressing males more during the second year. Aggression was higher
between same-sexed partners than between opposite-sexed partners. Males engaged in more social interactions with males during
the second year than the first year of life. Males played more than females during both years. Males played more with males
during the second year than the first year, and males played with males more than did females during the second year. We conclude
that sex differences in behavioral frequencies become evident during the first year of life, and sex differences in partner
preferences emerge during the second year of life. 相似文献
94.
95.
The assimilation of nitrate under dark-N2 and dark-O2 conditions in Zea mays leaf tissue was investigated using colourimetric and 15N techniques for the determination of organic and inorganic nitrogen. Studies using 15N indicated that nitrate was assimilated under dark conditions. However, the rate of nitrate assimilation in the dark was only 28% of the rate under non-saturating light conditions. No nitrite accumulated under dark aerobiosis, even though nitrate reduction occurred under these conditions. The pattern of nitrite accumulation in leaf tissue in response to dark-N2 conditions consisted of three phases: an initial lag phase, followed by a period of rapid nitrite accumulation and finally a phase during which the rate of nitrite accumulation declined. After a 1-h period of dark-anaerobiosis, both nitrate reduction and nitrite accumulation declined considerably. However, when O2 was supplied, nitrate reduction was stimulated and the accumulated nitrite was rapidly reduced. Anaerobic conditions stimulated nitrate reduction in leaf tissue after a period of dark-aerobic pretreatment. 相似文献
96.
Generation of natural killer-like cytotoxicity from human thymocytes with interleukin-2 总被引:1,自引:0,他引:1
Human thymocytes cultured in the presence of an interleukin-2 (IL-2) source (the supernatant of the MLA 144 cell line) that contains no lectin or interferon (IFN) activity become cytotoxic to K562 target cells. Inclusion of allogeneic lymphoblastoid cells in these cultures results in the earlier detection of cytotoxic activity. Addition of IFN to the thymocyte cultures has no effect on the development of cytotoxic activity. In contrast, the cytotoxic activity of IL-2 activated thymocytes can be augmented by subsequent exposure to IFN. The specificity and cell surface phenotype of the cytotoxic thymocytes are similar to that of peripheral blood natural killer cells. 相似文献
97.
ATP-induced Ca2+ release from the purified sarcoplasmic reticulum Ca2+-ATPase has been monitored in several different ATPase environments. Arsenazo III was used as a Ca2+ indicator in stopped-flow experiments and was shown to detect the early burst in Ca2+ transport, slower steady-state transport, and release of Ca2+ from fragmented sarcoplasmic reticulum. ATP-induced rapid release of Ca2+ followed by a slower rebinding step could be demonstrated for purified Ca2+-ATPase in leaky vesicles if the reaction was slowed by lowering the pH to 6.1 and by including dimethyl sulfoxide in the reaction medium. At a dodecyl octaoxyethylene glycol monoether (C12E8) to protein weight ratio of 0.2, a detergent concentration too low for solubilization to occur, ATP-induced Ca2+ release occurred more rapidly than for native leaky membranes, whereas the rebinding step was slower. In contrast, no Ca2+ release was observed for any soluble preparation. The kinetics of Ca2+ release was studied under conditions where the ATPase was monomeric or aggregated, and also in the presence of added phospholipid. The ATPase was shown to be monomeric by sedimentation equilibrium measurements in the presence of Ca2+, ADP, and beta, gamma-methylene-ATP at a C12E8 to protein weight ratio of 2.0. It is concluded that solubilization of the Ca2+-ATPase may result in uncoupling of ATP hydrolysis from ATP-induced Ca2+ release. 相似文献
98.
H. J. Dargie Marjorie E. M. Allison A. C. Kennedy Mary J. B. Gray 《BMJ (Clinical research ed.)》1972,4(5834):196-198
Metolazone is a modified quinazolinesulphonamide and in a dose of between 4 and 7·5 mg is an effective diuretic in man with normal renal function. Fourteen patients with non-oedematous stable chronic renal failure (creatinine clearance ranging from 1·2 to 12 ml/min) were given metolazone in doses ranging from 20-150 mg. A noticeable increase in urine flow and sodium excretion occurred, free water clearance increased, and there was a small but significant increase in potassium excretion. No side effects were noted. 相似文献
99.
We present absorption and circular dichroism (CD) spectra for the synthetic polymers poly d(AAT):d(AAT) and poly r(AAU):r(AAU), in both native and heat-denatured forms. As a means of evaluating the first-neighbor hypothesis, the CD spectra are compared with approximations derived from spectra of other synthetic polymers containing the same first-neighbor sequences. This is the first instance where such a comparison has been possible using spectra of double-stranded RNA sequences, and the agreement between the measured and approximated spectra for poly r(AAU):r(AUU) is surprisingly good. We have also subjected the CD spectrum of poly d(AAT):d(AAT) to a previously published analytical procedure for obtaining estimates of first-neighbor frequencies. In this first independent test of the procedure, we find that the analysis does infer the existence of a majority (86%) of AA, TT, AT, and TA first neighbors but does not precisely indicate their relative proportions. 相似文献
100.